my fire simulation is not reflecting the right way
The issue comes from how you mix the things together. In your second layer, the volume domain is excluded, so it's not rendered.

A way to go arround this is to render everything from one layer, but instead of mixing two layers, we will mix different passes of one layer according to object IDs, thanks to the ID Mask node.

Here's my version:



I'm sure it's not the best solution, but it's all I can think of.